Numerical Ability
Divisibility by 11 — Alternating sum of digits must be 0 or divisible by 11. Example: 121 → 1−2+1=0, divisible. Quick check for large numbers in data interpretation.
BODMAS Left-to-Right Trap — Division and Multiplication have equal priority (left-to-right), as do Addition and Subtraction. 20÷5×2 = (20÷5)×2 = 8, NOT 20÷10=2.
Percentage-Fraction Quick Converts — 12.5%=1/8, 16.67%=1/6, 33.33%=1/3, 62.5%=5/8, 87.5%=7/8. Memorize these; they speed profit-loss and discount problems enormously.
Alligation Shortcut — For mixture problems: draw a cross, write mean in center, cheaper/dearer at ends. Ratio = (Dearer−Mean):(Mean−Cheaper). Instant solution without equations.
Compound Interest ≈ SI + (SI²/200P) — For 2 years, CI approximately equals Simple Interest plus (SI squared divided by 200 times Principal). Useful when options are far apart.
LCM×HCF = Product of Two Numbers — If two numbers given and one measure asked, use this identity instantly. Example: LCM=60, one number=12 → other = 60×HCF/12.
Speed-Distance: Relative Speed — Same direction: subtract speeds; opposite direction: add speeds. Trains crossing, boats upstream/downstream—master this for 2-3 guaranteed marks.
Digit Sum for 3 and 9 — Number divisible by 3 (or 9) iff digit-sum divisible by 3 (or 9). Eliminates options in series, simplification, and number-system MCQs within seconds.
Mensuration: Circle in Square Waste — When circle inscribed in square of side *a*, wasted area = a²(1 − π/4) ≈ 0.215a². Memorize 21.5% waste for instant MCQ elimination.
Time-Work: M₁D₁H₁/W₁ = M₂D₂H₂/W₂ — MDH formula (Men×Days×Hours per Work) solves all variations. If men double and days halve, work remains same. One formula, all time-work problems.
Average: New Average Shift — When one element added, new average = old average ± (difference from old avg)/(n+1). Saves recalculation in data-interpretation tables.
Geometry: Angle-Sum Polygon — Sum of interior angles = (n−2)×180°. For hexagon: 4×180°=720°. Each exterior angle of regular polygon = 360°/n. Two formulas, all polygon MCQs covered.
Logical Reasoning and Mental Ability
Blood Relations: SAMDHI Code — Sister/Son = self generation; Aunt/Uncle = parent generation; Mother/Father = +1 generation; Daughter = −1 generation; Husband/Wife = spouse (same gen). Decode any complex chain.
Direction Sense: NEWS Clockwise — North→East→South→West rotates clockwise; right-turn goes next letter, left-turn goes previous. Starting North, two rights = East. Instant orientation fixes.
Coding-Decoding: +N Pattern — If CAT=DBU (each letter +1), check consistent shift across alphabet. A=1, B=2... Z=26 reverse coding (A=26) also common. Spot the rule in 10 seconds.
Calendar: Odd Days Method — Ordinary year=1 odd day, leap=2. Century years: 1600,2000=0 odd; 1700,1800,1900=5 odd. Count cumulative odd days mod 7 for weekday. January 1, 2000=Saturday anchor.
Syllogism: Venn Diagram Two-Circle — "All A are B" → A circle inside B. "Some A are B" → overlapping circles. Draw quick sketch; conclusion validity becomes visual and error-proof.
Alphanumeric Series: +5/−3 Toggle — Many series alternate add-5, subtract-3 or similar. AB5, CD8, EF5, GH8... spot the letter-pair +2 and number toggle pattern separately.
Clock Angle: |30H − 5.5M| — Angle between hands = |30×hour − 5.5×minutes|. If >180°, take 360−angle. At 3:15 → |90−82.5|=7.5°. Formula eliminates guesswork.
Ranking: Total = Sum + 1 — If A is 7th from top and 15th from bottom, total students = 7+15−1=21. Subtract 1 (A counted twice). Saves confusion in order/ranking MCQs.
General Knowledge and Current Affairs
BRICS Nations Mnemonic: BRICS — Brazil, Russia, India, China, South Africa. New 2023 entrants (UAE, Egypt, Ethiopia, Iran) often tested; keep updated list ready for international current affairs.
Bharat Ratna Chronology: First Three — C. Rajagopalachari, Sarvepalli Radhakrishnan, C.V. Raman (all 1954). Recent: Pranab Mukherjee (2019), Vajpayee/Madan Mohan Malaviya (2015). Anchor awards memory by decades.
Punjab Rivers: SRBCJ — Sutlej, Ravi, Beas, Chenab, Jhelum (west to east, five tributaries of Indus). Sutlej longest in Punjab. Bhakra Dam on Sutlej, Pong Dam on Beas—link river to infrastructure.
Ancient History Mnemonic: MHGK — Maurya→Harsha→Gupta→Kushan chronologically wrong; correct: Maurya(BC)→Kushan(AD early)→Gupta(AD 320)→Harsha(AD 606). MKGH timeline anchor avoids confusion.
Indian Economy: Budget Terms FD-RE-BE — FD=Fiscal Deficit (Expenditure−Revenue+Borrowing). RE=Revised Estimate (mid-year correction). BE=Budget Estimate (Feb projection). Distinguish these in banking/economy MCQs.
Environment: RAMSAR Wetlands India — Chilika (Odisha), Keoladeo (Rajasthan), Harike (Punjab), Wular (J&K), Loktak (Manipur). Punjab's Harike Wetland (Sutlej-Beas confluence) frequently appears in state-focused GK.
Punjab — History, Culture and Geography
Five K's of Sikhism: KKKKK — Kesh (uncut hair), Kangha (comb), Kara (bracelet), Kirpan (sword), Kachera (shorts). Mandatory articles; expect MCQs on Sikh identity and Khalsa initiation (1699 by Guru Gobind Singh).
Punjabi Folk Dances: BGKG-Giddha — Bhangra (men, harvest), Giddha (women), Kikli, Gatka (martial). Bhangra tied to Baisakhi festival (April 13/14). Link dance to occasion for culture questions.
Punjab Climate: Three Seasons — Summer (April-June, hot), Monsoon (July-Sep, SW monsoon rain), Winter (Nov-Feb, cold). Sutlej-Beas doab most fertile. Climate determines cropping pattern (wheat-paddy cycle).
Gurudwaras: Golden Temple = Harmandir — Harmandir Sahib (Amritsar), Takht Sri Patna Sahib (Bihar), Anandpur Sahib (Punjab). Five Takhts (temporal seats); Amritsar's Akal Takht is supreme. Foundation 1577 by Guru Ram Das.
**